1) Field of the Invention
The invention relates to a mooring system comprising a first vessel for containing hydrocarbons having at its bow and/or stern a transverse arm and a fluid transfer means comprising a duct connected to a tank on the first vessel and a coupling end for connecting to a second vessel, the second vessel being moored alongside the first vessel and being attached via a cable, extending from its bow in the length direction of the vessel, to a mooring end of the arm, which mooring end of the arm is substantially situated at or near a longitudinal centreline of the second vessel.
2) Description of the Related Art
Such a mooring system is known from EP 1 413 511, which shows a side-by-side mooring configuration of a permanently moored vessel and a tanker vessel, which is attached to the permanently moored vessel via a transverse arm extending from the latter. The tanker is moored to the arm via an inelastic mooring line, whereas the arm is resiliently hingeable around a vertical axis. A piston provides a restoring force on the arm, and allows pivoting or the arm, during use, when the vessel exerts a pulling force on the hawser. When the vessel rides up against the arm, it can freely rotate out of the way of the vessel.
The known mooring system has as a disadvantage that the position of the tanker will change in a sideways direction upon an excursion in the length direction of the tanker relative to the permanently moored vessel. The offloading arm for the hydrocarbons needs to make a relatively large excursion.
The present invention has as an object to provide a side-by-side mooring system of the above-mentioned type which can connect two vessels in relatively high sea states and allows the vessels to remain moored in a defined relative position while transferring hydrocarbons from one vessel to the other in high sea states.
It is another object of the present invention to provide a mooring system which maintains a stable configuration and a relatively large safety distance during hydrocarbon transfer in high sea states.
It is again an object of the present invention to provide a mooring system using a substantially mid-ship position of the hydrocarbon transfer duct-or ducts without being subject to large excursions.